In epidemiologic studies, associations of cardiovascular risk with individual and neighborhood socioeconomic characteristics tend to persist after adjustment for established cardiovascular risk factors suggesting that other mediators may be involved. However, evidence regarding what these mediators may be is largely absent. Elucidating the reasons for these persistent socioeconomic differences may enhance our ability to reduce these differentials and will contribute to our understanding of the causes of cardiovascular disease generally. Two biological processes, inflammation and hemostasis, have recently emerged as potentially important in the development of atherosclerosis and the precipitation of clinical cardiovascular events. Both processes have also been recently linked to psychosocial factors and stress. However, studies investigating social gradients in inflammation and hemostasis remain rare. In addition, the relation of psychosocial factors and biological markers of the stress response to inflammation and hemostasis have not been examined in large population-based studies. The overall goal of this epidemiologic study is to advance our understanding of how inflammation, hemostasis, and stress may contribute to neighborhood and individual-level socioeconomic differences in cardiovascular risk. Using newly collected data linked to an ongoing epidemiologic study of atherosclerosis (the Multi-Ethnic Study of Atherosclerosis (MESA)), we propose to investigate (1) associations of neighborhood and individual-level socioeconomic indicators with markers of inflammation and hemostasis; (2) associations of individual-level psychosocial factors and sources of chronic stress (at the individual and neighborhood level) with inflammatory markers and hemostasis; and (3) the relationship between biological markers of the stress response (such as cortisol and adrenaline/noradrenaline) and inflammation and hemostasis). Project aims will be achieved by linking MESA data to newly-collected data on neighborhood characteristics and biomarkers of inflammation, hemostasis and the stress response in MESA participants. The project is innovative in that it will span and link three levels: the social/environmental level (neighborhood characteristics and social position), the behavioral/psychological level (behavioral and psychosocial factors), and the biological level (inflammation, hemostasis, and stress hormones). The study will provide a unique opportunity to elucidate the links between socioeconomic factors, stress, inflammation and hemostasis in a large and diverse population-based sample.